Oh god, I want to be a girl so bad.

Can there be another gender transformation?

Hmmm I think that strap on became something else.

Well, we are talking a Succubus.
In addition to draining the essence from humans through sex, they also dominate them through their dreams.

Our slave girl is probably still manacled to the foot of the bed and there is no way for her to evade her mistress.

She's definitely still asleep. There's no way her chains suddenly vanish after being shown to be incredibly solid and effectively escape-proof and very little reason to believe she's capable of unrestraining herself after what we've seen from her in similar restraints earlier in the story. She would've had golden opportunity to possibly escape during the mistress's bath if she could.

With this font I read Haahhnn as "Heather", thought that might have been her new name.

Do my eyes deceive me? Futaaaaa!

:D